Note: Descriptions are shown in the official language in which they were submitted.
8~
1 FIELD OF THE INVENTION
This invention relates to a device (and control
circuitry therefor) for connecting in series between a
source of electric power and an appliance which, without
modifying the normal power connections or other parts of
the appliance, isolates the capacitance to ground characteristic
of the appliance from the power supply and allows the flow
of electrical power to the appliance to be regulated by
a mere touch, usually by a human finger, to a surface of
the appliance. The device comprises an electrical power
control circuit for regulating the supply of electrical
power to an appliance in response to a change in the capacitance
of the body of the appliance to ground between when the
body of the appliance is touched and not touched. The
function is accomplished by only making the normal electrical
power connection and without altering the appliance or
its insulation system in any way.
BACXGROUND OF THE INVENTION
Power control circuits for regulating the supply
of electric power to an appliance in response to a person
touching, or grounding the body of the appliance to ground,
are known, wherein the body of the appliance is part of
the power circuit. It is known to interpose impedance
components between the normal power supply of the appliance
and the body of the appliance in order to reduce the power
supplied to the body of the appliance to a safe level. Physical
connection with the power circuit via these im~ = s
-- 1 --
6~33
1 is still necessary, however, in order for a person to regulate
the power supplied to the appliance by touching the body
of the appliance. Examples of power control circuits comprising
physical connectlon with the power circuit may be seen
in United States Letters Patents 3,919,596; 4,163,923;
and 4,211,959.
It is therefore an object of this invention -to
provide a power control circuit for regulating the supply
of power to an appliance in response to touch that is safer
than such circuits heretofore, which have required physical
connection with the power circuit.
It is a further object of this invention to provide
a power control circuit for regulating the supply of power
to an appliance in response to touch, wherein the impedance
of its electrical conductors to the body of the appliance
is the normal insulation system of the appliance, which
is known to be safe.
It is a further object of this invention to provide
a power control circuit for regulating the supply of power
to an appliance in response to touch whereby the power
control circuit may be safely connected to the appliance
without altering or adapting the normal insulation and
circuitry of the appliance.
Further and other objects of the invention will
be apparent to those skilled in the art from the following
Summary of the Invention and Description of a Preferred
Embodiment of the Invention.
SUMMARY OF THE INVENTION
According to one aspect of the invention, a device
is provided for being connected in series between a source
-- 2
33
1 of electrie power and an appliance (for example, a lamp),
comprising:
(I) a series electrical power circuit comprising
(a) a beginning eleetrieal eonneetor, sueh as one side
of a male plug, for making the conneetion to one side of
an eleetrieal power supply;
(b) an eleetrieal power regulator, sueh as a triac, for
inereasing or deereasing the flow of power to the deviee;
(e) a first impedanee eireuit network, whieh may have a
parallel eonneeted inductive branch and capacitive branch,
one side thereof eonnected to the eleetrieal power regulator
and the other side connected to a first appliance electrical
connector, such as one side of a female receptaele;
(d) a seeond impedance circuit network which may have a
parallel conneeted inductive braneh and eapacitive branch,
one side of th~ second impedance circuit network (preferably
identical to the first impedance circuit network), the
first side thereof eonneeted to a second applianee eleetrical
eonnector sueh as the other side of the aforementioned
female reeeptacle, the second side of the second impedanee
eircuit being i~ turn eonneeted to a last eleetrical connector,
such as the other side of said male plug, for making the
connection to the other side of the electrical power supply,
and
(II) an electronic sensing and power regulator control
cireuit eomprising:
(a) a sensing eireuit network, eonneeted to the said applianee
eonneetors, for providing an eleetrieal signal, such as
a voltage that is a measure of the capaeitanee to ground
eharacteristie of a connected applianee, said sensing cireuit
~6G~83
1 network providing differences in the electrical signal
(voltage) between when the surface of the appliance is
touched by a human finger and when the appliance is not
touched, the sensing circult network in one embodiment
being constructed using a phase locked loop integrated
circuit and associated resistors and capacitors
(b) an electrical signal processing network which takes
the changes in the previously mentioned electrical signal
and converts them into digital "l"'s and "O"'s, in one
embodiment being constructed using, in series, an active
filter and a rate operated comparator and
(c) a memory and control circuit network which converts
the digital output information of the electrical signal
processing network into a control signal for the said electrical
power regulator, in one embodiment such circuit comprising
a series connection of a flip-flop and a triac gating optical
isolator.
According to another aspect of the invention,
a device is provided for connecting in series between a
source of electrical power and only an appliance's power
connection which regulates the supply of electrical power
to the appliance in response to a mere touch of the appliance
usually by a person's finger, said device comprising:
(a) an electrical connector for interposing the device
between the current-carrying components of the appliance
and the power supply;
(b) an electric power regulator for increasing or
decreasing the electric power provided to said appliance;
(c) an electrical impedance network for electrically
including the appliance within the impedance network when
33
1 the device is connected between the source of electrical
power and the appliance which impedance network means has
a very low lmpedance to power supply frequencies and a
high impedance to higher frequencies;
(d) an electronic sensing circuit for sensing the
distributed capacitance to ground characteristic of the
appliance as an electrical signal;
(e) an electronic signal processing network to condition
the said electrical signal and;
(f) a memory and control circuit network to convert
changes in said electrical signal into control signals
for said electric power regulator.
According to another aspect of the invention,
a module is provided for connecting in series by plugging
into the domestic electricity supply and plugging a standard
household portable lumiere (lamp) into the module which
regulates the supply of electrical power to the lamp by
a touch to the lamp, said module comprising:
(a) a first and second male blade for plugging into
the electricity supply and a first and second female connector
for receiving the male plug of the lamp which, in combination,
form an electrical connector means for interposing the
module between the lamp and the electrical power supply;
(b) a triac as an electrical power regulator means,
(c) a first and second impedance circuit network
being the parallel connection of an inductor and a capacitor,
said impedance circuit networks being arranged in series
sequence of first impedance circuit network, first female
connector for one side of lamp male plug, second female
connector for other side of male lamp plug, second impedance
~%69~33
1 circuit network in combination being the impedance network;
(d) a phase locked loop circuit network connected
to the common point of said second female connector and
second impedance circuit network, operating at a high frequency
which maintains the said impedance network in a resonant
mode thus having a first voltage level at a node in the
network when the lamp is not touched and a second voltage
level at said node when the lamp is touched;
(e) a voltage signal processing circuit which is
a series connectlon of an active filter and a rate operated
comparator to yield an output of digital "0" on said first
voltage level and a digital "l" on said second voltage
level;
(f) a memory and control circuit network means made
up of a flip-flop with one output coupled to a triac gating
optical isolator which is in turn operably connected to
the triac enabling sequential "on" and "off" of the lamp
with a series of touches to the lamp.
In one embodiment the said flip-flop is an integrated
circuit and associated components that is responsive to
both the fact of a digital "l" and its duration to provide
a ramped dimming up or down of the lamp lighting level
as well as "on" and "off" in response to touch of the lamp.
In another embodiment the said flip-flop is an
integrated circuit and associated components that is responsive
to digital "l"'s and "O"'s to provide a multi-step lighting
level of say three or four steps in response to touches
of the lamp.
According to another aspect of the invention
an electrical device is provided for regulating the supply
83
1 of power to a lamp having a normal insulation system wherein
any conductive parts of the body of the lamp are electrically
insulated from the components of the lamp carrying current
from the power supply, by the normal insulating system
of the lamp the device comprising:
(a) a male connector plug for connecting to power
supply (for example, low frequency AC supply or DC power
supply);
(b) at least a pair of parallel circuits having inductive
branches and capacitive branches and a female plug receptacle
to which the male plug elements of the lamp are received,
the receptacle interposed in the pair of parallel circuits
each having an inductive branch and capacitive branch thereby
including the conductive parts of the body of the lamp
when electrically connected to the device as part of the
capacitive branch of the parallel circuits.
A power control circuit for regulating the supply
of power to an appliance in response to a change in the
impedance of the appliance to ground when the appliance
is touched or grounded, and when in the untouched state,
the device for being interposed between the current-carrying
components of the appliance and a power supply, the device
comprising an impedance network and electrical means for
interposing the appliance within the network, the impedance
network comprising at least a pair of parallel circuits
each having an inductive branch and a capacitive branch
whereby the capacitance to ground of the capacitive branch
is increased by the capacitance to ground of a person touching
the body of the appliance, the parallel resonant frequency
of the network thereby changing, which provides a signal
~ 3~3
1 for regulating the supply of power to the appliance, the
body of the appliance being lnsula-ted from the power supply
by the normal insulation system of the appliance, thus
providing a safer method of controlling the power to the
device.
According to another aspect of the invention,
a device is provided for regulating the supply of electrical
power to an appliance comprising:
(a) electrical means for interposing the device between
the current-carrying components of the appliance and the
power supply;
(b) electrical means for locating the appliance within
an impedance network when the device is interposed between
the appliance and the power supply which has very low impedance
to power supply frequencies and a high impedance to higher
frequencies;
(c) electrical means for characterizing as an electrical
signal the impedance of the appliance to ground without
altering the normal insulation or assembly systems of the
appliance;
(d) electrical means for sensing the change in impedance
of the appliance to ground between when the appliance body
is touched and the appliance body is not touched; and
(e) means responsive to the sensed change in the
impedance to ground of the appliance for increasing or
decreasing the power supplied to the current carrying components
of the appliance.
According to another aspect of the invention,
a device is provided for regulating the supply of electrical
power to a lamp having a normal insulation system which
8 --
33
1 allows reyulation when any of the conductive parts of the
body of the lamp which are electrically insulated by the
normal insulation system of the lamp from the components
of the lamp carrying current from the power supply are
touched or grounded, the device comprising:
(a) electrical means for interposing the device between
the current-carrying components of the lamp and an electrical
power supply;
(b) circuit means comprising at least a pair of parallel
circuits having inductive branches and capacitive branches,
and means for locating the lamp within the parallel circuits
having the inductive branches and capacitive branches whereby
the conductive parts of the body of the lamp become included
as part of the capacitive branches of the said parallel
circuits;
(c) circuit means which provides a source of a high
frequency low power signal via the power conductors of
the lamp to the body of the lamp located within the at
least pair of parallel circuits whereby in the untouched
state a resonant frequency is established and which circuit
means characterizes the impedance to ground of the body
of the lamp as an electrical signal (for example, a voltage);
(d) circuit means for sensing the change in the electrical
signal (for example, voltage) which characterizes the change
in the impedance to ground between when a conductive part
of the body of the lamp is touched and a conductive part
of the body of the lamp is not touched, as an electrical
signal; and
(e) circuit means for increasing or decreasing the
power supplied to the current-carrying components of the
33
1 lamp in response to a change to the electrical signal (for
example, voltage~ which characterizes the change in the
impedance to ground.
An embodiment of the invention will now be illustrated
with reference to the following drawings, which is adapted
for touch activated regulation of the electrical power
supplied to a household lamp. Schedule "A" following the
Description of the Preferred Embodiment of the Invention
lists the components identified by number in Figures l,
2, 3, 4, 5, and 6 hereinafter referred to.
BRIEF DESCRIPTION OF THE DRAWINGS
.
Figure l is a pictorial view of a device (module)
constructed according to a preferred embodiment of the
invention being plugged into a wall outlet and a lamp being
plugged into the module.
Figure 2 is an exploded view of the device (module)
in Figure l.
Figure 3 is a drawing of the electrical circuit
of the preferred embodiment of the invention shown in Figures
l and 2 including connection to a power supply and a lamp.
Figure 4 is a detail electrical block diagram
of the phase locked loop and its associated components
forming part of the electrical circuit of the device shown
in Figures l and 2.
Figure 5 is an electrical schematic diagram of
a circuit which may be used to replace a portion of the
circuit shown in Figure 3, thereby providing a full range
of "on", "off" and intermediate dimming control.
Figure 6 is an electrical schematic diagram of
a circuit which may be used to replace a portion of the
-- 10 --
1~6~
1 circuit of Figure 3, thereby providing a "tri-light" control
action.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
_
With reference -to Figure 1 there is shown device
or module 101 constructed according to an embodiment of
the invention, shown in its operating environment. In
operation the male connectors 110 and 111 of device 101
are plugged into the wall receptacle 102 power supply and
the lamp 103 is plugged into the female receptacle 104
f the module 101, thus making contact with the -female
connectors 112,113 contained therein. The arrangement
of the female connectors 112,113 of module 101 is more
clearly shown in the e~ploded view of Figure 2.
A detailed circuit configuration of the embodiment
of the invention contained within module 101 will now be
described in conjunction with Figure 3. The circuit consists
of two principal parts; the first, a series connected
electrical power circuit, which performs the functions
of connecting to the power supply and to the lamp, regulating
the power to the lamp and isolating the capacitance to
ground characteristic of the lamp from the power supply;
the second, an electronic sensing and memory/control circuit
for the power regulator which performs the functions of
sensing the capacitance to ground characteristic of the
lamp as a voltage, converting change in this characteristic
as a result of touching the lamp into digital signals and
finally using the digital signals to activate a memory
storage device whose output controls the power regulator
in the power circuit.
The power circuit is connected via male blade
-- 11 --
-
1 110 to one side oE the power supply 1 which is the domestic
electricity supply at 120 volts 60 Hertz. This supply,
by its nature, will have a distributed capacitance 12 to
ground of several thousand picofarads and may in fact be
grounded at one side 13. In series with blade 110 is a
triac 4 bypassed by parallel capacitor 11 of 10,000 picofarads.
Connected in series with the triac 4 is one side of a first
impedance circuit network made up of inductor 7 of 250
microhenries and capacitor 8 of 500 picofarads, connected
in parallel. The other side of said first impedance circuit
network is connected to a first female connector 113, then
in series the lamp 3, and a second female connector 112.
Connector 112 connects to one side of a second impedance
circuit network consisting of inductor 5 of 250 microhenries
and capacitor 6 of 500 picofarads connected in parallel
- the second side of which is connected to a second male
blade 111 and thence to the other side of the power supply
1. The first and second impedance circuit networks make
up electrical impedance network 2, which includes the lamp
3 along with its distributed capacitance to ground shown
as capacitor 14 (typical values approximately 30 to 90
picofarads). The inductors 5 and 7 are made with wire
able to carry the full load current of the lamp, typically
#20 AWG for a 300 Watt lamp bulb.
The electronic sensing circuit begins with the
phase locked loop network consisting of phase locked loop
10 and its associated capacitors 17, 18, 19 and resistors
20, 21, 22, 23, 24 that operate to present a frequency
at node 9 which will be the particular resonant frequency
of the impedance network 2/lamp capacitance 14 combination,
- 12 -
33
1 typically about 450 kilohertz for the values of the circuit
devices chosen. (A more complete explanation of the operation
of the phase locked loop portion of the circuit is presented
in conjunction with Figure 4 hereafter). By the operation
of the phase locked loop network, the voltage at node 16
is a direct linear function of the frequency at node 9.
A normal value is about 10 volts at node 16 for 450 kilohertz
at node 9. When a person's body capacitance of approximately
50 to 300 picofarads is brought into contact with a surface
15 of the lamp, by touching the lamp, this increases the
value of capacitor 14. This increased value of capacitor
14 means the resonant frequency presented at node 9 by
the phase locked loop network is decreased and the voltage
at node 16 is decreased, typically by 0.2 to 0.4 volts.
Similarly, when the touch is removed, the voltage at node
16 goes back to the previous higher level.
The capacitor 11 is a high frequency bypass capacitor
provided to enable operation of the sensing circuit in
the event that the electrical power supply is reversed.
The changes in voltage at node 16 are processed
by operational amplifiers 29 and 38 and their associated
capacitors and resistors to yield a digital "]" at node
40 when node 16 voltage is moved lower (lamp touched) and
a digital "0" at node 40 when node 16 voltage is high (lamp
untouched)-
The processing is done in two stages. The firststage through operational amplifier 29 and its associated
capacitors 27,28, resistors 25,26 form a low pass active
filter to attenuate electronic noise at node 16 and the
second stage through operational amplifier 38 and its associated
6~33
1 capacitor 30 and resistors 31, 32, 33, 34, 35, 36, 37 which
form a rate activated comparator with noise suppressing
hysterisis such that when a change of level at node 39
of more than about 0.1 volts happens with a fall or rise
rate of more than about 2 volts per second, operational
amplifier 38 changes the signal at node 40 as described
above. The signal at node 40 is connected to flip-flop
41. Flip-flop 41, such as one-half a type 4013 flip-flop
will put node 42 alternately at "1" or "0" for each "1"
appearing at node 40. This signal at 42 is fed via resistor
43 to the light-emitting diode of triac gating optical
isolator 44. When the light-emitting diode is energized
by a digital "0" at node 42, its light triggers on the
triac of 44 which in turn provides gate power via resistor
45 to triac 4, thus turning on the lamp 3. If a digital
"1" is at node 42, no power is provided to the optical
isolator and the lamp 3 remains off.
~ power supply 46 furnishes low voltage, low
power direct current as required to operate the electronic
devices.
The effect of this embodiment is to alternately
turn the lamp on and off at each time a ~etal part of the
body of the lamp is touched.
Referring now to Figure 4r an explanation of
the operation of the phase locked loop network is presented.
A block diagram of a phase locked loop integrated
circuit 10 as manufactured by Motorola Semiconductors and
others as type 4046 is shown. The device consists of two
main parts, a voltage controlled oscillator (VC0) and a
phase comparator (A second phase comparator, a source follower
- 14 -
33
1 and a zener regulator lncluded in this integrated circuit
are not used and have only been shown dotted for completeness.)
The VCO circuit is connected through pins 4,
5, 6, 7, 9, 11, and 12. When a capacitor 17 of 50 picofarads
is connected to pins 6, 7, resistors 21 and 22 of 120 kilohms
each are connected to pins 11, 12, and pin 15 is connected
to OV as shown then a square wave output of OV to +15V,
of frequency range of approximately 350 to 500 kilohertz
will appear at pin 4 as direct linear function of the voltage
at pin 9 in the range OV to +15V.
The phase comparator is connected through input
pins 3 and 14 and output pin 13. This circuit compares
the frequency and phase relationship between the leading
edge of an input signal at pin 14 wi-th the leading edge
of a reference input signal at pin 3 to produce an output
at pin 13. The output at pin 13 is continually high (-~15V)
if the frequency at pin 14 is higher than the reference
signal frequency at pin 3. Similarly, the output at pin
14 is continually low (OV) if the frequency at pin 14 is
lower than the reference input at pin 3. If the frequencies
at pin 14 and pin 3 are identical, then the output at pin
13 is a pulse at the input frequency whose width is proportional
to the phase difference between the leading edges of the
two input signals. This pulse is positive going if the
phase of the signal at pin 14 is lagging the signal at
pin 3 and the pulse is negative going if the signal at
pin 14 is leading the signal at pin 3. The amount of phase
difference between the inputs to range the output from
a virtual full positive pulse (+15V) to a virtual full
negative (OV) pulse is about one degree.
- 15 -
~L2~ 3
1 Using these two portions of the integrated circuit
10 and connecting them together as shown in Figure 4; output
pin 4 of VCO directly connected to phase comparator input
pin 3; output pin 4 connected via resistor 24 to node 9
of impedance network 2 (lamp combination made up of parallel
capacitive and inductive branches); node 9 connected via
capacitor 18 to input pin 14; output pin 13 connected to
node 16 by resistor 20; node 16 connected via capacitor
19 to OV of the power supply and via resistor 23 to input
9 of the VCO; results in a closed loop feedback circuit
network.
This circuit functions as follows: when initially
powered, the voltage at node 16 is at OV, thus the output
frequency at pin 4 is at the minimum of 350 kilohertz as
described above and the impedance network 2 lamp combination
will be below resonance; this below resonance means that
the phase of the signal at node 9 will be lagging that
of the VCO; as network 2 is separated from the VCO output
(pin 4) by resistor 24; since VCO output 4 is connected
directly to phase comparator input pin 3 and node 9 is
connected via capacitor 18 to phase comparator input pin
14, the output, at pin 13, is virtually +15V and capacitor
19 (0.22 microfarads approx.) is charged via resistor 20
(470 kilohms approx.); by this charging, node 16 increases
in voltage which in turn increases the output frequency
of the VCO; at some specific frequency, say 450 kilohertz,
the impedance network 2/lamp combination will move towards
resonance meaning that the signal at node 9 will move towards
being in phase with the signal of the VCO and thus the
phase comparator output will start to proportion the width
- 16 -
1 of its output pulse; by the integrating action of the resistor
20/capacitor 19 combination exactly the correct amount
of voltage is maintained at node 16 to keep these input
signals to the phase comparator in phase; if the frequency
of the VCO is too high for resonance, as when the added
capacitance of a person touching the lamp is included,
then the signal phase at node 9 leads the VCO and output
13 of goes to OV, discharging capacitor 19 until a correct
lower voltage at node 16 keeps the impedance network 2/touched-lamp
combinatlon in resonance. These actions take approximately
two to five milliseconds to be complete. In this manner
the voltage at node 16 provides a signal which indicates
whether the lamp is not touched or touched.
By removing the existing network of Fig. 3 between
nodes 40 and 42 and interposing between nodes 40 and 42
various networks or devices that respond to number, sequence,
frequency, duration or combination thereof of the digital
"l"'s and "O"'s that appear at node 40 as a result of touches,
a variety of switching, dimming, control and timing sequences
of the lamp are easily achieved and contemplated for the
use of the invention in a preferred embodiment. For example,
by replacing flip-flop 41 by integrated circuit chip S576
as manufactured by Siemens Components Inc. and making the
necessary connections as shown in Figure 5, the full range
of "on", "off" and dimming described for the S576 may be
utilized. A second example of replacing flip-flop 41 with
the network shown in Figure 6 would result in a "tri-light"
action wherein the lamp would come on dimly at the first
touch, more brightly at the second touch, brightest at
the third touch and off again at the forth touch.
~ 13
1 Other means of characterizing the impedance of
the lamp to ground may be used without departing f rom the
embodiment of the invention, as for example utilizing at
node 9 circults other than a phase locked loop, such as
a charge pumping circuit; pulse response circuit; and an
oscillator circuit triggered on or off.
As many changes can be made to the embodiment
of the invention without departing f rom the scope of the
invention, it is intended that all material be considered
as illustrative of the invention and not in a limiting
sense.
- 18 -
